The present invention relates to a ball screw. Ball screws convert rotational movements into translatory movements. The present invention also relates in particular to an actuating device for actuating a brake, in particular parking brake for a motor vehicle.
EP 1058795 B1, for example, discloses an actuating device for a parking brake of a motor vehicle, in which actuating device a ball screw is provided.
The threaded spindle, which is driven by an electric motor and which is comprised of a plurality of spindle parts, effects a relative axial displacement between the threaded nut and the threaded spindle, wherein the threaded nut, in its feed direction, exerts a pressure force on a friction pad of a disk brake. This pressure force is absorbed via an axial bearing on the housing, on which axial bearing the threaded spindle is supported. On account of the axial pressure forces exerted, elastic deformations may occur in the housing, which elastic deformations may cause tilting between the threaded spindle and the threaded nut or tilting between the threaded spindle and the axial bearing. Such tilting may impair the functionality of the ball screw.